Valve operating linkage lubrication and hydraulic valve lifter feed system for engines



Feb. 6, 1962 D. B. KUIPER 3,019,857

vALvE OPERATING LINKAGE LUBRICAIIDN AND HYDRAULIC VALVE LIETER FEED SYSTEM FOR ENGINES Filed June 22, 1959 United States Patent() 3,019,857 VALVE OPERATING LINKAGE LUBRICATIGN AND HYDRAULIC VALVE LIFTER FEED SYS- TEM FOR ENGEES Dan B. Kuiper, Grand Rapids, Mich., assigner to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed June 22, 1959, Ser. No. 822,143 Claims. (Cl. 184-6) This invention relates to internal combustion engines and the like, and particularly to the valve operating mechanism thereof.

Use of hydraulic valve lifters in engine valve operating mechanisms has posed problems in providing a satisfactory supply of hydraulic iiuid for the lifters. The most' common practice is to supply the lifters with oil from the regular engine lubricating system, but this places undesirable limitations on the medium best suited either for use in the lifters or as lubricant in the engine. For example, it is frequently desired to use oil in the lifters lwhich is of different viscosity from. that of the lubricating oil in the engine, particularly when the engine oil must be varied with change in atmospheric tempera` tures, or where chemical properties which would enhance the engine oil are not suitable as hydraulic lifter fluid. On the other hand, it is frequently desirable to operate the hydraulic valve lifters for short periods with fluids which will purge them of dir-t and varnish deposits, without having to similarly treat the entire engine lubricating system. Also, because of the conventional practice of using special lubricating oils during the initial break-in of a new engine, it is frequently necessary to protect the hydraulic valve lifter parts with zinc or manganese phosphate coa-tings, etc., which adds to their cost of manufacture. Further, when the hydraulic valve lifters are fed from the engine lubricating system it is impossible to employ a higher viscosity oil in the lifter to compensate for faster leakdown resulting from wear, without also subjecting all the engine bearing surfaces to the same high viscosity oil -which may be undesirable for various reasons.

In view of these problems, serious efforts have been made to develop hydraulic valve lifters containing their own supply of iiuid in a sealed-up reservoirA built into the lifter, however, difl'iculty in providing a satisfactory seal to prevent loss of this fluid, as well as the increased cost of such lifters, has been a deterrent to their commercial use. Also, such self-contained type lifters do not eliminate all the problems above referred to.

It is accordingly the principal object of my invention to provide a self-contained lubrication and hydraulic valve. lifter iiuid supply system for the valve operating linkage whereby the most desirable oils or other fluids to be used therein and in the main lubricating system of the engine may be individually selected.

It is also an object of the invention to enclose the conventional camshaft in an oil filled pumping chamber into which the hydraulic valve lifters move inwardly and outwardly as plungers in response to camshaft rotation, with the oil pressure created in this chamber by the inwardly moving lifters serving to pump oil therefrom to lubricate the valve operating mechanism and feed the lifters without intermixture with the main engine lubricating oil in the crankcase, etc.

The means by which these and other objects and advantages of the invention are attained will be more readily apparent from the following description of one embodiment thereof selected for illustration, having reference to the drawing showing a transverse sectional view through a V-type internal combustion engine incorporating the separate lubricating and hydraulic lifter feed system in accordance with the invention.

3,019,857 Patented Feb. 6, 1962 rice Referring now in detail to the drawing, the numeral 1 indicates the crankcase of a V-type internal combustion engine having a working cylinder 2 open at itslower end to the crankcase and closed at its upper end by a conventional cylinder head 3. Within the working cylinder 2 is the usual piston 4 connected to the crankshaft 5 by a connecting rod 6. Control of Working iluid admission and exhaust from the combustion space 7 above the piston is by means of conventional poppet valves, the stem of one of which is shown at 8. Actuation of this valve stem to its open position (shown) is eected by an actuator or rocker journaled on a shaft 10 supported from the cylinder head 3. Suitable bearing means in the form of ia bushing 1i between the shaft and the rocker 9 is provided which requires lubrication'during engine operation. Valve return (closing) means in the form of the usual valve spring 12 is provided, which reacts between the cylinder head 3 and a spring retainer 13 fixed to the valve stem 8. Rocking movement or" the rocker in the valve opening direction is effected by the usual engine riven camshaft 14 whose motion is transmitted to the rocker by a hydraulic valve lifter 15 and hollow push rod i6.

The hydraulic valve lifter 15 is of conventional design having a hollow plunger-like outer body 17 within which is slidably fitted an inner plunger 13, which is also hollow to provide a reservoir chamber 19 for hydraulic liuid. Resting on the upper end of the inner plungeris a push rod seat Zh having a lifter fluid receiving passage 21 extending centrally thcrethrough which connects with an opening 22 in the lower end of the push rod 16. The push rod has a similar opening.23 atl its upper end'which connects with an internal passage 24 extending through the rocker from the bearing surface of the bushing 11. A cored passage 25 extends into the cylinder block 26 and connects at its upper end with other passages 27, 28, 29 and 30 extending through the cylinder head and rocker shaft to the interior of the rocker 10, from which a radial passage 31 extends to the bearing surface of the bushing 11. p

An oil pumping chamber 32 is provided which encloses the camshaft 14. This cham-ber is formed by walls or baffle members 33 and 34 located above and below the camshaft and extending longitudinally and transversely of the engine between the inner side walls 35 and 36, the end wall 40, and the opposite end wall (not shown) of the engine cylinder block 26. As is conventional, the side walls 35 and 36 are provided with thickened sections or bosses 37 opposite the camshaft, which bosses are provided with bores 38 for reciprocably guiding the lifter bodies 17 in their movement with rotation of the camshaft. Both the upper and lower bafiies or wall members 34, 33 have their marginal edges suitably sealed as by welding to the abutting surfaces of the cylinder block end and side walls. The upper baie member 34 cooperates with the side and end walls of the cylinder block in forming a sump for the pumping chamber 32 and which is isolated thereby from the crankcase below, the oil level in this sump being indicated by broken lines at 41.

The upper batile or wall member 34 has a one-way ow connection for passage of oil therethrough from the sump into the chamber 32, which connection is shown in the form of an aperture 42 closable from the chamber side by a ball check valve 43. A lubricant passage for one-way flow outwardly of the chamber 32 is provided by a second aperture 44 and connects via a fitting 45 with an oil line 46 leading to the cored cylinder block passage 25. Return flow into the chamber 32 via this passage is prevented by an outwardly opening ball check valve 47. Y

During engine operation, oil is pumped outwardly of anlass? the chamber 32 via the aperture 44, fitting 45, line 46 and passages 25-30 to the rocker shaft, from which it is delivered to the bearing surfaces of the bushing 11 via the rocker shaft port 31. Lubricant within the bushing 11 returns via the rocker shaft passage 24, through the push rod to the lifter iiuid receiving passage 21 in the push rod seat 2f! for vdelivery to the lifter reservoir chamber 1,9. Oil supplied from this reservoir to .the pressure chamber (not shown) below the inner plunger 18 of the lifter is subjected to compression during each outward stroke of the lifter in conventional manner, with the result that a. small amount of leakage escapes between the sliding surfaces of the lifter plunger 18 and body 17 and is collected in the sump above the upper bafe 34.

Although only one such lifter is illustrated in the drawing, it will be understood that a plurality of such iifters operate in plunger-like fashion within the pumping chamber 32, whereby a continuous pumping action takes place.

While only a single preferred embodiment of the invention has been disclosed, it is appreciated that numerous changes inthe construction and arrangement of the parts may be made without departing from the spirit and scope of the invention as defined in the following claims.

I claim:

l. In an internal combustion engine or the like having a valve, a valve rocker, a rocker operating hydraulic valve lifter and lifter operating cam means, said lifter including an outer plunger-like body engaging said cam means, a lubricating and fluid feed system for said rocker and lifter including wall members defining a fluid pumping chamber enclosing the cam means, one of said wall members having an opening therein slidably embracing said lifter body, said plunger-like body being movable inwardly of said chamber from said opening to displace fluid from said chamber during the return stroke of said cam means, and one-way iiuid passage means connecting said chamber with said rocker exteriorly of said lifter for conducting said displaced fluid to said rocker. K

2. In an internal combustion engine or the like having at least one working iiuid cylinder, a workingrfiuid control valve, operating mechanism for said valve including a valve actuator, bearing means supporting said actuator, cam means driving said actuator and a hydraulic valve lifter operatively interconnecting said actuator and cam means, said lifter having a hydraulic fluid receiving passage, and a closed hydraulic lubricating and feed System for said bearing means and lifter receiving passage, said system comprising a hydraulic fluid pumping chamber enclosing said cam means, said lifter having an outer plunger-like body movable into and out of the chamber in response to operation of said cam means, land fiuid passage means interconnecting said chamber and lifter passage via said bearing means, said passage means having a check valve openable to permit flow therethrough of fluid displaced from said chamber Vby said plunger-like body during its movement inwardly of said chamber.

3. In an internal combustion engine or the like having a crankcase, wall members defining a pumping chamber therein and a sump isolated from the crankcase by said pumping chamber, a one-way flow connection from the sump to the pumping chamber, a camshaft rotatable in the pumping chamber, a hydraulic valve lifter including a plunger-like outer body having one end extending into the pumping chamber land engaging the camshaft and its opposite end extending into said sump, a valve rocker and a bearing therefor externally of the crankcase, a push rod connecting said rocker and. valve lifter, a one-,way iiow lubricant passage connecting said pumping chamber and rockerbearingand lubricant return means from said bearing to the sump, said return means including a passage extending longitudinally through the push rod and a chamber Within the-valve lifter communicating with said push rod passage and said sump respectively.

4. In an internal combustion engine or the like having at least one working fluid cylinder, a working fluid control valve, operating mechanism for said valve including a valve actuating rocker, a rocker bearing, a rocker actuating push rod, a push rod actuating hydraulic valve lifter, a camshaft drivingly engaging said lifter and valve return means, a lubricant supply passage leading to said rocker bearing, a lubricant return passage extending via said rocker from said bearing to the adjacent end of said push rod, said push rod having an opening extending longitudinally therethrough and continuing said return passage to said lifter, said lifter having a plungerlike outer body open at its end adjacent said push rod, a plunger slidable in said body, said plunger having a push rod seat abutting the adjacent end of the push rod and a lubricant receiving passage connecting with said push rod opening, walls defining a lubricantpump chamber enclosing the camshaft, a body of lubricant filling said chamber, other walls cooperating with one of said chamber defining Walls in defining a lubricant sump adjacent the chamber, one of said chamber defining walls having an opening through which the closed end ofv said lifter body extends into the chamber to engage the camshaft, an outlet flow connection from said chamber to said lubricant supply passage, an inlet iiow connection to said chamber from said sump, and non-return iiow means in eachl of said flow connections.

5. In an internal combustion engine or the like having a valve, a valve actuator, a hydraulic valve lifter operatively connected to said actuator, and cam means operatively driving said lifter, a self-contained lubricating and iiuid feed system for said actuator and lifter including wall members defining a fluid pumping chamber enclosing the cam means, one of said wall members having an opening therein slidably guiding said lifter, said lifter having a plunger-like body movable inwardly of said chamber from said opening to displace-duid from said chamber during the return stroke of said cam means, and one-Way passage means accommodating flow of said displaced liuid from said chamber to said lifter via said actuator and back to said chamber from said lifter.

References Cited in the file of this patent UNITED STATES PATENTS 1,741,230 Goodwin Dec. 3l,l i929 2,366,701 Doman Jan. 9, 1945 2,657,679 Powell Nov. 3, 1953 

